On Wednesday 03 May 2006 16:42, Jeff Dike wrote:
> Do we really need to pull that into the UML Kconfig? We need some of
> the things it defines, like X86_CMPXCHG, but people keep discovering
> that menu and trying to set it to match the host, causing compilation
> problems when that pulls in headers that UML doesn't have.
Yes, I didn't fix these problems. I've been fairly lazy, I must admit this.
> I think I would like to dump Kconfig.cpu and define for ourselves the
> symbols that we need.
How do you let the user choose the CPU he wants to optimize for? That was the
first purpose of what I did - optimizing for 386 isn't exactly the best thing
to do (and we've done this, till the menu was introduced).
We can restrict the choices in the menu, for now, with a dependency on ! UML
for the ones which don't work (i.e. the ones using 3DNow in string
operations, IIRC). M686, Athlon and likely Pentium 4 work at least.
--
Inform me of my mistakes, so I can keep imitating Homer Simpson's "Doh!".
Paolo Giarrusso, aka Blaisorblade (Skype ID "PaoloGiarrusso", ICQ 215621894)
http://www.user-mode-linux.org/~blaisorblade
Chiacchiera con i tuoi amici in tempo reale!
http://it.yahoo.com/mail_it/foot/*http://it.messenger.yahoo.com

Do we really need to pull that into the UML Kconfig? We need some of
the things it defines, like X86_CMPXCHG, but people keep discovering
that menu and trying to set it to match the host, causing compilation
problems when that pulls in headers that UML doesn't have.
I think I would like to dump Kconfig.cpu and define for ourselves the
symbols that we need.
Jeff

On Monday 01 May 2006 17:57, Abhay Raghu wrote:
> i) Can you please explain the difference between PTRACE_SYSCALL and
> PTRACE_SYSEMU?
Download latest man-pages (at least 2.27) and read man 2 ptrace; if something
is not clear, I'll answer to your further doubts.
> ii) This question is related to uml: How do all applications run within a
> single userspace thread?
Doing context switching is fairly easy: with ptrace you change all registers
and so on. I guess you know that, if I'm wrong feel free to ask.
There is a further problem however: different apps have different address
spaces, with different mappings (or different memory images, they're running
different executables with different libraries... there are various way to
say this).
To solve this problem, we introduce on the host the SKAS3 patch whihch allows
one process to have multiple address spaces - only one is in use, but via
ptrace(PTRACE_SWITCH_MM) we can replace that one with another one - this is
done by making a pointer in the process descriptor (i.e. current in Linux
kernel code) point to another "mapping set" (called struct mm_struct), so
it's very fast; you must also invalidate the TLB (i.e. the processor caches
of page table entries) like on any "memory context switching", obviously.
--
Inform me of my mistakes, so I can keep imitating Homer Simpson's "Doh!".
Paolo Giarrusso, aka Blaisorblade (Skype ID "PaoloGiarrusso", ICQ 215621894)
http://www.user-mode-linux.org/~blaisorblade
___________________________________
Yahoo! Mail: gratis 1GB per i messaggi e allegati da 10MB
http://mail.yahoo.it

I have a new email address!You can now email me at: sarahstanley101@...
We are experts in the sale of raw materials and we export into Canada and America and some parts of Europe. We are searching for reliable representatives who can help us establish a medium of getting to our customers in the Canada and America as well as legally receiving cash and all forms of payment on our behalf from them as our Representative. Please if interested in transacting business in view of helping us, so our clients could be making payment to you as our representative, we will be very glad. Compensations will be given and other benefits. Contact us for more information, if this proposal is acceptable to you. Please get back to me, so that remuneration can be worked out for your services as our representative in Canada and America as your location shall determine. For further information and inquiries: Contact Mr. Paul Thomas (Consultant) paul_thomas450@... Import & Export Company Tel: 0044 703 181 8799. We anticipate your earliest response in this regard. Thank
- sarah stanley

Community

Help

Get latest updates about Open Source Projects, Conferences and News.

Sign up for the SourceForge newsletter:

CountryState

JavaScript is required for this form.

I agree to receive quotes, newsletters and other information from sourceforge.net and its partners regarding IT services and products. I understand that I can withdraw my consent at any time. Please refer to our Privacy Policy or Contact Us for more details